SEO pour soplanning

Bonjour
Je suis tombé sur votre profil et ai rédigé mon annonce en anglais avant de me rendre compte que vous êtes francophone :)

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I'm the owner of SOPlanning ([URL visible pour les membres Pro]).
I'm a very small company and want now to be more visible in US (already correct SEO in France).

There are about 8000 visits per month, not so big but correct for a small open source project. i can share GA data if needed.

I let you discover the tool on the website, my goal is to get better results on Google for those keywords : online planning, free planning, planning software, online schedule, and some other ones you could help me to identify.
What could you propose me in term of strategy, advises on the website (i have 100% control on the content and can change texts, structure, etc), action plan, and price ?

Contact me for any other informations you need.

Thanks